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The ownership split (design/display-management.md §3): the registry owns the per-session virtual-display lifecycle on Linux, so a display can outlive its session (keep-alive) and be reused on reconnect. - registry.rs: a Linux pool driven by the pure lifecycle machine. acquire() reuses a kept (lingering/pinned) display of the same backend+mode, else creates one and keeps the backend's keepalive so the compositor output (and its PipeWire node_id) survives the session. The session's capturer holds a gen-stamped DisplayLease instead of the real keepalive; its drop drives linger/teardown. Enabling fact: KWin/Mutter/gamescope put their node on the DEFAULT PipeWire daemon (remote_fd=None) — reconnect re-attaches by node_id, no fd re-open. wlroots (remote_fd=Some, xdpw portal) passes through unchanged (teardown-on-drop) pending the fresh-portal-capture re-attach. - Default (unconfigured) linger = Immediate → today's teardown-on-disconnect, so no behavior change without a keep-alive policy; concurrent sessions still each create their own output (reuse only matches LINGERING entries). - Wired build_pipeline (punktfunk1) + gamestream through registry::acquire; capture_virtual_output signature unchanged. Windows delegates to vd.create (the manager already leases) — unchanged. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>